Ultrasound image display set-up for remote display terminal

ABSTRACT

An ultrasound system enables simplified setup of a remote terminal for display of ultrasound images acquired by the ultrasound system. An image acquired by the ultrasound system is processed by or with display parameters for different viewing conditions or devices, such as display gamma correction, ambient lighting, or image quality. A plurality of versions of an image with slightly different display appearances are exported to the remote terminal, where a viewer can view all of the image versions simultaneously. The viewer selects the best image, and the display characteristics of the selected image are used for images subsequently exported from the ultrasound system to the remote terminal.

This application is the U.S. National Phase application under 35 U.S.C.§371 of International Application No. PCT/IB2013/053788, filed on May10, 2013, which claims the benefit of U.S. Provisional Application No.61/650,241 filed on May 22, 2012. These applications are herebyincorporated by reference herein.

This invention relates to medical diagnostic ultrasound systems and, inparticular, to the export and display of images from an ultrasoundsystem to a remote display terminal such as a review station on a PACS(picture archiving and communication) system.

A typical ultrasonic imaging system will have dozens of control settingwhich can be adjusted by a user to best display an image of anatomy ofthe body. For instance, when imaging tissue a sonographer will be ableto set the line density, focal zones, dynamic range, transmit andreceive frequencies, resolution penetration, transmit power, sectorwidth, grayscale mapping, number of multilines, and numerous otherimaging variables. When imaging blood flow in the colorflow mode some ofthe imaging variables which may be adjusted are wall filter settings,color map, frame rate, velocity range, frequency compounding, filtersettings, and Doppler steering angle. With so many possible settings itis not surprising that ultrasound systems have control software thatstores parameter presets for different types of imaging exams. Asonographer starting an obstetrical exam, for example, can select thepresets for an OB exam and the ultrasound system will invoke a set ofpresets commonly used for most OB exams. The sonographer may besatisfied and use the system-selected presets, or can adjust the presetvalues and save the new set of presets as his or her preferred presetsfor a particular patient or type of exam.

Unless a sonographer is always satisfied by the system presets for anexam type, even customizing and saving sets of preset parameters fordifferent exams can be a time consuming task. Moreover even custompresets can become unsatisfactory or obsolete as equipment is upgradedand new probes become available for standard exams. However, U.S. Pat.No. 6,951,543 (Roundhill) has provided a solution to this problem. Thatis to process an ultrasound image with a variety of different parametervalues, such as the standard system preset values and common variationsthereof. The sonographer does not have adjust numerous parameters andcontrols and see what difference each incremental or new parametervariation produces. Instead, the sonographer views a gallery of images,each of which has been processed by at least a slightly different set ofacquisition or image processing parameters. The sonographer then simplypicks the image that looks the best, and the parameters of that imageare then applied for a particular exam. The selection process is farsimpler than painstakingly adjusting numerous ultrasound systemparameters.

The reading of ultrasound images in order to arrive at a diagnosis of adisease condition often does not occur on the ultrasound system whichacquired the images. In many hospitals and clinics a sonographer mayacquire the ultrasound images by scanning a patient, and the images ofthe patient are then transmitted to a diagnostic workstation or terminalwhere a cardiologist or radiologist will view the images, make adiagnosis, and prepare a diagnostic report. At times the images may bestored on a PACS archive server from which a physician can access theimages for diagnosis. The workstation or terminal where the images areread may be equipped with special diagnostic software such as the QLABdiagnostic ultrasound analysis software package available from PhilipsHealthcare in Andover, Mass., USA, which facilitates the diagnosis ofultrasound images and the reporting of a diagnosis. When images areviewed on a new terminal or display screen, they are often not viewedunder the same conditions as they were on the ultrasound system whichacquired the images, causing subtle anatomic differences to appeardifferently. The review workstation or terminal may be in a more dimlyor brightly lighted room, for instance, which will affect the appearanceof the images in other environments. Different display screens willcause subtle image differences, as will the image file size and imagecompression which may be used to archive images. The physician could gothrough an adjustment procedure to optimize the images on the reviewterminal (e.g., GSDF) but this is usually not done due to its complexityand the time involved in evaluating different display options. Manydoctors simply accept the factory default settings on their terminalsand settle for sub-optimal images. Accordingly there is a need tosimplify the optimization of a workstation, terminal or display screenfor the optimal viewing of diagnostic ultrasound images which have beenexported from the acquiring ultrasound system.

In accordance with the principles of the present invention, a diagnosticultrasound system has a setup procedure that optimizes images fordisplay on remote workstations, terminals, and display screens. Theultrasound system enables a user to select one ultrasound image acquiredon the ultrasound system which is exported to a remote display terminalwith a number of different display settings applied to the image. A useron the remote display terminal views a gallery of the same image withdifferent display settings such as different display gamma correction,file sizes, brightness and/or contrast. The user then selects the imagefrom the gallery with the best appearance on the remote terminal and thedisplay parameters of the selected image are stored on the ultrasoundsystem. Each time a new image or images are exported to the terminal,they are thereafter sent with the selected display settings, assuringthat they will be remotely displayed as the remote user desires. Shouldthe remote user have a change of mind or a new display with differentcharacteristics be installed, the process can repeated to update thedisplay parameters applied to images exported to the remote terminal.

In the drawings:

FIG. 1 illustrates in block diagram form an ultrasound systemconstructed in accordance with the principles of the present invention.

FIG. 2 illustrates an ultrasound system networked with a PACS system.

FIGS. 3a-3f illustrate display screens for setting up an ultrasoundsystem on a network with user preferences for exported images.

FIG. 4 illustrates a method for setting up and exporting a gallery ofimages with different display settings to a remote terminal.

FIG. 5 illustrates a gallery of images with different display settingswhich are presented to a user for selection of the best image.

Referring first to FIG. 1 an ultrasonic diagnostic imaging systemconstructed in accordance with the principles of the present inventionis shown in block diagram form. An ultrasound probe 112 includes anarray 114 of ultrasonic transducers that transmit and receive ultrasoundsignals. The array may be a one dimensional linear or curved array fortwo dimensional imaging, or may be a two dimensional matrix oftransducer elements for electronic beam steering in three dimensions.Three dimensional image data sets and images are preferably acquiredusing a two dimensional array transducer. Three dimensional images mayalso be acquired with a mechanically swept one dimensional array probe.The ultrasonic transducers in the array 114 transmit ultrasonic energyand receive echoes returned in response to this transmission. Atransmit/receive (“T/R”) switch 22 is coupled to the ultrasonictransducers in the array 114 and switches between the transmit andreceive phases of pulse-echo imaging. The times at which the transducerarray is activated to transmit signals may be synchronized to aninternal system clock (not shown), or may be synchronized to a bodilyfunction such as the heart cycle, for which a heart cycle waveform isprovided by an ECG device 26. When the heartbeat is at the desired phaseof its cycle as determined by the waveform provided by ECG device 26,the probe is commanded to acquire an ultrasonic image. The frequency andbandwidth of the ultrasonic energy transmitted by the transducer arrayis controlled by control signals generated by a central controller 28.

Echoes from the transmitted ultrasonic energy are received by thetransducers of the array 114, which generate echo signals that arecoupled through the T/R switch 22 and digitized by analog to digital(“A/D”) converters 30 when the system uses a digital beamformer. Analogbeamformers may also be used. The A/D converters 30 sample the receivedecho signals at a sampling frequency controlled by a signal f_(S)generated by the central controller 28. The desired sampling ratedictated by sampling theory is at least twice the highest frequency ofthe received passband, and might be on the order of at least 30-40 MHz.Sampling rates higher than the minimum requirement are also desirable.

The echo signal samples from the individual transducers of the array 114are delayed and summed by a beamformer 32 to form coherent echo signals.For 3D imaging with a two dimensional array, it is preferable topartition the beamformer between a microbeamformer located in the probeand the main beamformer in the system mainframe as described in U.S.Pat. No. 6,013,032 (Savord) and U.S. Pat. No. 6,375,617 (Fraser). Thedigital coherent echo signals are then filtered by a digital filter 34.In the illustrated system the transmit frequency and the receiverfrequency are individually controlled so that the beamformer 32 is freeto receive a band of frequencies which is different from that of thetransmitted band such as a harmonic frequency band. The digital filter34 bandpass filters the signals, and can also shift the frequency bandto a lower or baseband frequency range. The digital filter could be afilter of the type disclosed in U.S. Pat. No. 5,833,613, for example.Filtered echo signals from tissue are coupled from the digital filter 34to a B mode processor 36 for conventional B mode processing.

Filtered echo signals of a contrast agent, such as microbubbles, arecoupled to a contrast signal processor 38. Contrast agents are oftenused to more clearly delineate the endocardial wall in relation tocontrast agent in the blood pool of the heart chamber, or to performperfusion studies of the microvasculature of the myocardium as describedin U.S. Pat. No. 6,692,438 for example. The contrast signal processor 38preferably separates echoes returned from harmonic contrast agents bythe pulse inversion technique, in which echoes resulting from thetransmission of multiple pulses to an image location are combined tocancel fundamental signal components and enhance harmonic components. Apreferred pulse inversion technique is described in U.S. Pat. No.6,186,950, for instance.

The filtered echo signals from the digital filter 34 are also coupled toa Doppler processor 40 for conventional Doppler processing to producevelocity and power Doppler signals. The output signals from theseprocessors may be displayed as planar images, and are also coupled to a3D image processor 42 for the rendering of three dimensional images,which are stored in a 3D image memory 44. Three dimensional renderingmay be performed as described in U.S. Pat. No. 5,720,291, and in U.S.Pat. Nos. 5,474,073 and 5,485,842, all of which are incorporated hereinby reference.

The signals from the contrast signal processor 38, the B mode processor36 and the Doppler processor 40, and the three dimensional image signalsfrom the 3D image memory 44 are coupled to a Cineloop® memory 48, whichstores image data for each of a large number of ultrasonic images. Theimage data are preferably stored in the Cineloop memory 48 in sets, witheach set of image data corresponding to an image obtained at arespective time. The image data in a data set can be used to display aparametric image showing tissue perfusion at a respective time duringthe heartbeat. The sets of image data stored in the Cineloop memory 48may also be stored in a permanent memory device such as a disk drive ordigital video recorder for later analysis. The images in the Cineloopmemory are displayed on a display 52.

When a sonographer begins a particular ultrasound exam the sonographerwill generally start by selecting the appropriate probe for the exam,such as a phased array probe for a cardiac exam or a curved linear arrayfor an abdominal or OB exam. The sonographer may then set up and adjustall the imaging parameters for the exam by adjusting the switches andcontrols on the system control panel 150. Generally, however, thesonographer will configure the system by calling up the set of standardor previously customized parameters for the type of exam beingcommenced. These preset parameters are stored in a configuration datamemory 152 and are applied to the central controller 28 when selected bythe sonographer. The central controller then uses the imagingparameters, as adjusted by the sonographer, to set up and conduct theimaging procedure selected by the sonographer.

In larger hospitals and clinics the ultrasound system is generallyconnected to a network over which ultrasound images can be communicated.A network interface 54 enables the ultrasound system to communicate overthe network and is coupled to a network connection in the hospital orclinic. A typical network with a PACS system is shown in FIG. 2. In FIG.2, four ultrasound systems 102-106, a PACS image workstation 244, and aPACS network server 242 are connected in a local area network asindicated by LAN 240. The LAN 240 may be wired or wireless and mayinclude both Ethernet hub systems and multi-switch, multi-layerednetworks. The network server 242 for a PACS system will have extendedstorage 234 for retention of a large volume of ultrasound images andreports produced by the network's ultrasound systems and image reviewstations. A user at the image workstation 244 can access the networkserver and individual active ultrasound systems of the network, orinteract over the Internet with other externally accessible networks anddevices.

In accordance with the principles of the present invention theultrasound system of FIG. 1 is configured to export ultrasound imagesfor viewing on a workstation or terminal on a network by use of anexport configuration wizard illustrated in FIGS. 3a-3f . The startingscreen of FIG. 3a informs the user that the wizard will guide themthrough the selection of various export configuration choices for anoptimum configuration. The starting screen presents four topics forconfiguration. For an initial configuration all four topics are used. Ifthe user wants to adjust a configuration that has been implementedpreviously, the user is given the choice of selecting only the topic(s)to be modified. The subsequent drawings illustrate an initialconfiguration setup.

When the user clicks on the Next button of the starting screen theNetwork Configuration screen is presented as shown in FIG. 3b . On thisscreen the user can enter the identification of the network server. Thenext line on this screen allows the user to specify whether the DHCP(dynamic host configuration protocol) is being used, whether theultrasound system will have a fixed IP address on the network or avariable (dynamic) IP address assigned by the host server. If theultrasound system has a fixed IP address it is entered on the next line.

The user clicks the Next button and the PACs Configuration screenappears as shown in FIG. 3c . Here the user can select a PACS systemfrom a pulldown list that is on the network and already identified bythe wizard. Alternatively the user can click the Custom PACsConfiguration radio button and is presented with a screen for entry ofdata that defines a custom PACS configuration. The user clicks the Nextbutton and is presented with the FIG. 3d screen.

On the Image Quality and File Size Selection screen of FIG. 3d the userdefines one of the parameters that affects how images exported from theultrasound system appear on the screen of a workstation or terminal onthe network. The PACS system or other storage device may storeultrasound images with a predetermined amount of compression or a filesize limit. The size of the image file is directly related to theperceived image quality since finer detail can be shown in an image of alarger file size. In this example the user drags a slider 62horizontally to set the desired image quality. An arrow above the FileSize graphic moves correspondingly, showing the user the file sizerecommended for the desired image quality. The user will generallybalance the desired image quality and file size to obtain the highestquality images within the bounds of the permitted size of imagesarchived on the PACS system. The user clicks the Next button and ispresented with the screen of FIG. 3 e.

The Image Acquisition & Review Environment screen enables a user to setanother parameter that affects how images acquired by the ultrasoundsystem will appear on the remote terminal. The patient scanning room maybe only dimly lighted and consequently the user may employ lowbrightness and contrast settings to view the ultrasound images as theyare acquired. The physician reading the images may be viewing them in abrightly lighted room, which means that the view settings on theultrasound system will not be suited to the ambient lighting conditionsof the reading room. Or, the reverse may be true. With the screen ofFIG. 3e the user can adjust slider 64 to indicate the ambient lightingconditions in the scanning room as low, high, or intermediate. The usercan also check the GSDF (grayscale standard display function) box if thedisplay at the remote terminal has this DICOM calibrated displayfunction, in which case further display optimization is not necessary.

After the user has adjusted the last set of display parameters the useris presented with the closing screen of FIG. 3f . If the user hasfinished specifying the PACS and image export parameters the user canclick on the Finish button to conclude the export configuration process.If the user has encountered a problem or has a question, the user canclick on the question mark symbol to request technical assistance incompleting the configuration process.

With the export parameters and network protocols thus set, the user nowprepares an export of images that will be displayed with differentdisplay parameters as exemplified by the export screens of FIG. 4. Inthis set of screens, identified as the Export IQ Wizard, the user isguided through the acquisition of an ultrasound image and its exportwith different processing for viewing and selection on a remoteterminal. The first screen 70 instructs the user to prepare theultrasound system to scan an image under the condition generallypreferred by the user, such as in an appropriately lighted room. If thedisplay at the remote terminal is DICOM GSDF calibrated, thiscompensation procedure is not needed, however. The user will then clickthe DICOM GSDF Enabled radio button and proceed to Finish thiscompensation procedure, as indicated by screen 72.

When the user clicks the Continue button on screen 70 to proceed withthe compensation procedure, the user is shown screen 74. This screeninstructs the user to acquire an ultrasound image with the ultrasoundsystem. The user can do this by scanning a patient at this time, inwhich case the user will click the Continue button on screen 74 and willscan a subject. After the user has acquired a satisfactory image theuser presses Acquire 1 on the ultrasound system control panel 150.Alternatively, the user can select a previously acquired satisfactoryimage from the image storage on the ultrasound system. Again, the userindicates that a satisfactory image has been obtained by pressingAcquire 1 on the ultrasound system control panel 150.

With the basic compensation image identified, the user selects adestination to which compensation selection images are to be exportedusing screen 76. In this example the user has selected Archive Server 1,a PACS image storage device on the network where the images are storedwith the image processing employed by the PACS system. Screen 76 givesexamples of different export destinations including one called PC Mediafor ultrasound systems not connected to a reading station by a network.If this radio button is selected the screen 78 appears to instruct theuser to insert media into the ultrasound system such as a portable flashdrive. The images are then transferred to the flash drive which can becarried to the reading workstation for the compensation setup. In thisexample the user has selected Archive Server 1 and a set of compensationimages such as that of FIG. 5 is sent to the Archive Server 1 PACSsystem. Screen 80 is then displayed to the user, instructing the user toview the compensation images on the PACS system display terminal andselect the image that best represents the basic image acquired by orselected on the ultrasound system.

FIG. 5 is an example of a set of compensation images 200 that areexported to the PACS system and viewed on a review station on the PACSsystem such as terminal 244 in FIG. 2. Each of the twenty-fivecompensation images has been processed by the controller 28 or containsslightly different display parameters that will affect its appearance ona display screen. For instance, each of the twenty-five images can beprocessed by a slightly different display device gamma correctioncharacteristic. Or each image will have a slightly different brightnessor contrast to compensate for different ambient lighting conditions. Theuser views all twenty-five images simultaneously on the remote terminaldisplay screen and selects the one which appears the best on thatdisplay screen. The user can click on the up and down arrows in theselection box 210 at the bottom of the screen to select the number ofthe best image. In this example the user has selected image number 13.Alternatively the user can click on an image to select it, such asclicking on image 202 to select that image as the best compensatedimage. When the user makes the selection the identity of the selectionis sent back to the ultrasound system where the display parameters ofthe selected image are stored in a lookup table in the configurationdata memory 152 of the system in association with the export destinationdevice, Archive Server 1 in this example. Thereafter, whenever imagesare exported from the ultrasound system to Archive Server 1, the displayparameters stored in the lookup table in memory for that PACS system areapplied to the images prior to export so that they are properlycompensated to appear on the PACS terminal just as they appeared on theultrasound system. A reviewer on the PACS workstation will then beviewing an exported image with the same image quality andcharacteristics as seen by the sonographer who acquired the image.

Screen 80 of FIG. 4 also gives the user the ability to select thedesired image from the screen on the ultrasound system. The user canmake the selection on screen 80, then click the Finish button toconclude the image export compensation process.

A PACS system may have multiple review stations or terminals on thesystem and each may have a different display characteristic. In thatevent, the foregoing compensation process may be performed for eachdisplay device of each station or terminal. The ultrasound system willthen use the correspondingly identified display station when exportingimages for display on one of the terminals.

A review station or terminal can also be replaced or modified with adifferent display screen or used by a clinician with different viewingpreferences, requiring that the compensation be performed again for thenew or different display device or reviewer. In that event, the ExportIQ Wizard of FIG. 4 can be called up on the ultrasound system to send anew set of compensation screens to the terminal and the compensationselection process performed again and new display parameters for theterminal stored in the configuration data memory 152. Alternatively, theclinician at the review station can send a query to the ultrasoundsystem, requesting transmission of another set of compensation images.The user of the remote terminal can thereby adjust or update the displayparameters of images exported from the ultrasound system withoutinterrupting the workflow of the sonographer who is using the ultrasoundsystem.

The present invention has applicability in other medical imagingmodalities, particularly in the use of “secondary captures,” imageinformation which is derived from a primary diagnostic image. Forexample, an MRI image of the body may show an invasive instrument suchas a biopsy needle which a clinician wants to view in well definedresolution. The optimization technique of the present invention can beused to optimize the displayed images for optimal viewing of thissecondary capture, the needle in the MRI image.

What is claimed is:
 1. A diagnostic ultrasound system which compensatesimages exported to a remote display terminal comprising: a displayconfigured to effectuate presentation of one or more views of agraphical user interface, the one or more views comprising one or morefields configured to facilitate entry and/or selection, by a user, ofinformation related to one or more of a network configuration, a PACsconfiguration, an image quality selection, an image file size selection,or an ambient light level; an ultrasound image storage device whichstores an image of a single ultrasound image plane acquired by theultrasound system; an image processor which produces a plurality ofversions of the image of the single ultrasound image plane for export,each version having a different display appearance when the plurality ofversions of the image of the single ultrasound image plane are viewedsimultaneously; a remote terminal having a display screen on which theplurality of versions of the image of the single ultrasound image planeare displayed simultaneously; a selector, upon additional user inputselects one of the versions of the image of the single ultrasound imageplane; a data storage device which stores a parameter for the version ofthe selected image in association with an identifier of the remoteterminal; and an export processor which processes images for export tothe remote terminal with the parameter of the selected image.
 2. Thediagnostic ultrasound system of claim 1, wherein the parameter is one ofdisplay device gamma characteristic, image brightness or image contrast.3. The diagnostic ultrasound system of claim 1, wherein the remoteterminal further comprises a PACS system.
 4. The diagnostic ultrasoundsystem of claim 3, wherein the remote terminal further comprises a PACSsystem image archive.
 5. The diagnostic ultrasound system of claim 3,wherein the remote terminal further comprises one of a plurality ofworkstations of a PACS system.
 6. The diagnostic ultrasound system ofclaim 1, further comprising a network which connects the ultrasoundsystem and the remote terminal.
 7. The diagnostic ultrasound system ofclaim 1, wherein the remote terminal and the ultrasound system are noton a common network, wherein the plurality of versions of the image areexported to the remote terminal on portable media.
 8. The diagnosticultrasound system of claim 1, further comprising an input device bywhich ambient light condition data is input into the ultrasound system,wherein the image processor produces the plurality of versions of theimage for export in consideration of the ambient light condition data.9. The diagnostic ultrasound system of claim 1, further comprising aninput device by which image file size data is input into the ultrasoundsystem, wherein the image processor produces the plurality of versionsof the image for export in consideration of the image file size data.10. The diagnostic ultrasound system of claim 9, wherein the image filesize further comprises the file size of images stored on a network imagearchive.
 11. The diagnostic ultrasound system of claim 1, furthercomprising an input device by which image quality data is input into theultrasound system, wherein the image processor produces the plurality ofversions of the image for export in consideration of the image qualitydata.
 12. The diagnostic ultrasound system of claim 1, wherein the datastorage device stores the parameter for the version of the selectedimage in lookup table form.
 13. The diagnostic ultrasound system ofclaim 1, wherein the production of a plurality of versions of the imagefor export is initiated from the ultrasound system.
 14. The diagnosticultrasound system of claim 1, wherein the production of a plurality ofversions of the image for export is initiated from the remote terminal.15. The diagnostic ultrasound system of claim 1, wherein the datastorage device stores a plurality of parameters, each in associationwith an identifier of a different remote terminal; wherein the exportprocessor processes images for export in consideration of the identifierof one of the different remote terminals which is the destination ofexported images.